Tooth-bar.



PATENTED SEPT. 4, 1906.

T. O. BERG.

TOOTH BAR.

APPLICATION FILED 0011s. 1905.

W m 8 F N W3 M T .W M A. Wm m VI r B a H.

WITNESSES:

UNITED STATES PATENT OFFICE.

THORVALD O. BERG, OF LITTLE FALLS, MINNESOTA.

TOOTH-BAR.

To all whom it may concern.-

Be it known that I, THORVALD O. BERG, a citizen of the United States, and a resident of Little Falls, in the county of Morrison and State of Minnesota, have invented a new and Improved Tooth-Bar, of which the following is a full, clear, and exact description.

This invention relates to improvements in tooth-bars used in sawmills for shifting and turning logs, the object being to provide a tooth-bar formed in a single casting, thus iving it greater strength and rigidity than is found in bars made in several pieces riveted together, as such a bar is weakened on account of the great number of rivet-holes.

Another object is to provide the teeth with a guard to prevent line bark or the like from falling upon the pivots, thus preventing undue wear of the pivots.

Still another object is to provide a novel form of rivet for the teeth.

I will describe a tooth-bar embodying my invention, and then point out the novel features in the appended claims.

Reference is to be had to the accompanying drawings, forming a part of this specification, in which similar characters of reference indicate corresponding parts in all the views.

Figure 1 is'a side elevation of a tooth-bar embodying my invention. Fig. 2 is a longitudinal section thereof, on the line as w of Fig. 3. Fig. 3 is a front elevation, partly in section; and Fig. 4 is a section on the line g y of Fig. 2.

Referring to the drawings, 1 designates the body of the bar, which is formed in a single casting of suitable metal-such, for instance, as steel. The lower portion is tubular, as clearly indicated, and the upper portion is provided with openings 2, which extend from the front to the rear, and mounted to swing in these openings are teeth 3, said teeth being curved upward in the usual manner. The lower end of the bar 1 has divergent basearms 4, which connect with operating pistonrods 5, extended from pistons in cylinders 6. These arms 4, it will be noted, are connected by a base-bar 7, which gives strength to the lower portion of the device.

Specification of Letters Patent. Application fil d October 13,1905. Serial No. 282,673.

Patented Sept. 4, 1906.

The pivots for the teeth 3 have enlarged threaded portions 8 for engaging in tapped holes in walls of the openings 2, and the pins have reduced portions 9, which pass through erforations in the teeth and engage in perforations in the opposite wall. The pivotpins are inserted alternately from opposite sides, and therefore by alternately roviding small perforations in opposite wal s the bar is not materially meakened.

When in lowered position, the teeth rest upon brid e-plates 10, and at the heel portion of each tooth is a curved guard-finger or plate 11, designed to engage over and pass over the upper portion of a curved cross-bar 12. By this arrangement, and as the guards 11 extend entirely across the openings 2, they will prevent fine bark or the like from passing onto the pivot-pins.

The upper end of the bar has a head 13 formed integral with it, and this head is practically wedge-shaped, extending to a point 14, and below this point the front and rear sides are curved outward. By this construction the upper end may readily pass between logs when the tooth-bar is moved up or down.

Having thus described my invention, I claim as new and desire to secure by Letters Patent 1. A tooth-bar comprising a body portion having openings, teeth mounted to swing in the openings, bridge-pieces upon which the teeth may rest, and guards at the heel portions of the teeth to prevent material from reaching the pivot-pins of the teeth.

2. A tooth-bar having openings, teeth mounted to swing in the openings, the said teeth having rearwardly curved guard-plates at the heel portions, upwardly and forwardly curved cross-bars in the openings and over which said guards may swing, and bridges for supporting the teeth when in lowered position. 4

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

THORVALD O. BERG. Witnesses:

N. M. BERGnErM, HALL. 

